Alzheimer disease (AD) can impair the capacity of patients to give informed consent for research participation. Studies of informed consent involving other patient populations suggest better understanding of consent-relevant information may be achieved through modifications in the consent delivery process, including incorporation of multimedia learning tools into the consent discussion. The goals of this project are to evaluate the efficacy of an enhanced consent procedure for patients with mild-to-moderate AD, and to identify factors and patient characteristics that predict the degree to which enhanced consent is more beneficial than routine consent procedures. These goals will be addressed through a randomized comparison of enhanced versus routine consent procedures administered to 136 patients with mild-to- moderate AD patients and 136 age-comparable normal comparison subjects (NCs). Decisional capacity will be evaluated in reference to either of two (randomly assigned) hypothetical protocols, and willingness to participate will be assessed. Participants will be evaluated with a cognitive test battery;rating scales of neuropsychiatric symptoms and satisfaction with the consent process will also be administered. As capacity evaluations in applied settings ultimately require a dichotomous decision, participants will be categorized as decisionally capable or incapable of consent for the presented protocol, and we will evaluate the effects of consent condition on these categorization rates. We hypothesize that the enhanced consent procedure will result in better manifest decisional capacity, greater willingness to participate in the presented study, greater satisfaction with the consent procedure, and greater likelihood of being categorized as "capable of consent". We also hypothesize that cognitive abilities, particularly memory, will moderate the effectiveness of enhanced consent, with those in the extreme ends (very mild cognitive deficits or more severe cognitive deficits) showing less benefit than those in the mid-range. This project addresses important issues relating to informed consent for research, fitting within the goals of NIH PA # 02-103, seeking to support studies of "how features of the informed consent process affect participants'comprehension and/or willingness to participate in research." This study's relevance derives from the idea that enhanced consent may foster comprehension as AD patients are asked to provide consent or assent to participate in clinical research.